Background: To set up the review criteria for flow cytometry with CytoDiff (FCC) and evaluate the efficiency of different workflows using combinations of FCC with a hematology analyzer and microscopy.
Methods: Leucocyte differentials of the samples from 995 clinical specimens and 278 specimens from healthy donors were analyzed using a hematology analyzer, FCC, and microscopy.
Results: The correlations between the hematology analyzer, FCC, and microscopy were good for neutrophils, lymphocytes, and monocytes, but not in the case of basophils (r = 0.464, 0.358, 0.33) and eosinophils (r = 0.69, 0.67, 0.621). As a reference method of WBC differential using microscopy, the threshold of blasts for FCC was defined by a ROC curve at 1% (specificity 97.9%, sensitivity 97.5%, AUC 0.989). The optimal cutoff of immature granulocytes for FCC was 1% (specificity 85.8%, sensitivity 76.5%, AUC 0.866). The optimal cutoff of lymphocytes, neutrophils, and monocytes were 50%, 85% and 12%, respectively. According to the review criteria, the workflow of CBC after FCC and then microscopy had the highest sensitivity (97.07%), lower false negative rate (2.93%), and higher accuracy (80.3%) compared with others.
Conclusions: Our study integrated FCC into a WBC differential workflow in a routine laboratory and, for the first time, demonstrates the efficiency of different workflows. It can be used for reference in the selection of different hematology workflows.